Tube



FIG. 1 is a front and top perspective view of a tube showing my new design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a side elevation view thereof taken from the right of FIG. 2, the opposite side being a mirror image thereof;

FIG. 4 is a rear elevation view thereof; and,

FIG. 5 is a top plan view thereof. 

The ornamental design for a tube, as shown and described. 